Cross-Metathesis of Methallyl Halides: Concise Enantioselective Formal Total Synthesis of (-)-Presphaerene.

The cross-metathesis (CM) of methallyl halides catalyzed using four different ruthenium-based complexes-Grubbs catalyst, Grubbs second-generation catalyst, Hoveyda-Grubbs second-generation catalyst, and Stewart-Grubbs catalyst-was investigated. When methallyl chloride or bromide was reacted with a model substrate containing a benzyl ether group, the Grubbs catalyst, and Grubbs second-generation catalyst did not promote the reaction well. However, the Hoveyda-Grubbs second-generation catalyst and Stewart-Grubbs catalyst afforded the corresponding products in moderate to good yield with moderate / selectivity.

Identification of a new M-ALPHA analog and MDMA in an illegal health product.

The widespread abuse of illicit psychoactive substances is one of the most serious public health and social problems. A suspicious airmail package was seized by Korean customs, and two psychoactive substances in the grayish-green pills in the package were detected by ultra-performance liquid chromatography. The structures of the two substances were elucidated by a combination of liquid chromatography quadrupole time-of-flight mass spectrometry, nuclear magnetic resonance spectroscopy, and comparison with reported or newly generated spectral data of the suggested structures.

Potential Moracin M Prodrugs Strongly Attenuate Airway Inflammation .

This study aims to develop new potential therapeutic moracin M prodrugs acting on lung inflammatory disorders. Potential moracin M prodrugs (KW01-KW07) were chemically synthesized to obtain potent orally active derivatives, and their pharmacological activities against lung inflammation were, for the first time, examined using lipopolysaccharide (LPS)-induced acute lung injury model. In addition, the metabolism of KW02 was also investigated using microsomal stability test and pharmacokinetic study in rats.

Isolation and characterisation of a novel sildenafil analogue adulterant, desmethylpiperazinyl propoxysildenafil, in a dietary supplement.

A new sildenafil analogue was detected during routine screening of dietary supplements suspected to be adulterated with an erectile dysfunction drug(s) using HPLC-DAD. The UV spectrum of this compound was highly similar to that of sildenafil and almost identical to that of desmethylpiperazinyl sildenafil. The analogue was purified by using semi-preparative HPLC and structurally elucidated by performing mass spectrometric and NMR spectroscopic experiments.

Novel metabolites from Trichoderma atroviride against human prostate cancer cells and their inhibitory effect on Helicobacter pylori and Shigella toxin producing Escherichia coli.

The present study aimed to purify and identify the metabolites from T. atroviride using high-performance liquid chromatography (HPLC) and H and C nuclear magnetic resonance spectrometer (NMR) followed by analyzing their toxicological, antibacterial and anticancer properties. This work identified two metabolites - TM1 and TM2.

Stereoselective Protection-Free Asymmetric Total Synthesis of (+)-Chamuvarinin, a Potent Anticancer and Antitrypanosomal Agent: Substrate-Controlled Construction of the Adjacently Linked Oxatricyclic Core by Internal Alkylation.

A stereoselective protection-free asymmetric total synthesis of (+)-chamuvarinin (1), a potent anticancer and antitrypanosomal agent, has been accomplished. The adjacently linked [bis(tetrahydrofuran)]tetrahydropyran (THF-THF-THP) core of this natural product with seven stereogenic centers was constructed in a completely substrate-controlled fashion. The inter-ring stereochemistry ( threo,threo,threo) of the oxatricyclic core was established in a stereoselective fashion by a chelation-controlled Keck allylation, whereas the intraring cis or trans relative stereochemistry was controlled by a stereoselective internal alkylation.

Preservative effect of Chinese cabbage (Brassica rapa subsp. pekinensis) extract on their molecular docking, antioxidant and antimicrobial properties.

This study aimed at investigating the antimicrobial activity of different solvent extracts of Chinese cabbage Brassica rapa subsp. pekinensis (BRARP) and their antioxidant and cytotoxicity properties. Of the different solvents extracts, the chloroform extracts (CE) were significantly inhibited the bacterial pathogens at minimum inhibitory concentration (MIC) of 16.

Identification and characterization of an indazole-3-carboxamide class synthetic cannabinoid: 2-[1-(cyclohexylmethyl)-1H-indazole-3-carboxamido]-3,3-dimethylbutanoic acid (DMBA-CHMINACA).

Illicit psychoactive substances have threatened public health worldwide. An active metabolite of ADB-CHMINACA and MDMB-CHMINACA was identified for the first time in a powder-type product found in an airmail package. The structure of compound 1 was elucidated by a combination of gas chromatography-mass spectrometry (GC-MS), liquid chromatography-high resolution mass spectrometry (LC-HRMS), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy.

Collision-induced dissociation pathways of H-antihistamines by electrospray ionization quadrupole time-of-flight mass spectrometry.

Over the past decades, mass spectrometry technologies have been developed to obtain mass accuracies of one ppm or less. Of the newly developed technologies, quadrupole time-of-flight mass spectrometry (Q-TOF-MS) has emerged as being well suited to routine and high-throughput analyses of pharmaceuticals. Dietary supplements and functional foods have frequently been found to be contaminated with pharmaceuticals.

Synthesis and Structure Revision of Dimeric Tadalafil Analogue Adulterants in Dietary Supplements.

A number of phosphodiesterase 5 (PDE5) inhibitors approved by authorities have been used successfully in the treatment of erectile dysfunction. These medicines must be prescribed carefully due to their adverse effects, but they and their analogues are being illegally added to dietary supplements. These illegal dietary supplements pose a significant risk to public health.

Moracin M inhibits airway inflammation by interrupting the JNK/c-Jun and NF-κB pathways in vitro and in vivo.

The therapeutic effectiveness of moracins as 2-arylbenzofuran derivatives against airway inflammation was examined. Moracin M, O, and R were isolated from the root barks of Morus alba, and they inhibited interleukin (IL)-6 production from IL-1β-treated lung epithelial cells (A549) at 101-00μM. Among them, moracin M showed the strongest inhibitory effect (IC50=8.

Identification and structural elucidation of three new tadalafil analogues found in a dietary supplement.

Compounds elucidated as new tadalafil analogues were found to be adulterated in a dietary supplement and detected during routine analysis by HPLC with photodiode array detection. The UV spectra of these compounds were found to be almost identical to that of tadalafil. The unknown compounds were isolated by preparative HPLC and elucidated by quadrupole-time-of-flight MS and NMR spectroscopy.

Identification of a new tadalafil analogue in an adulterated dietary supplement: trans-Bisprehomotadalafil.

A new tadalafil analogue was identified along with homotadalafil during routine screening of an adulterated dietary supplement using HPLC-DAD. The UV spectrum of this analogue was almost identical with that of tadalafil. This compound was isolated from the supplement by using semi-preparative HPLC and its structure was subsequently elucidated by performing Q-TOF/MS/MS and NMR spectroscopic experiments.

Stereoselective synthesis of C18-guggultetrol and C18-phytosphingosine analogues from D-fructose.

A series of C(18)-guggultetrol stereo isomers and C(18)-phytosphingosine regio/stereo isomers were synthesised in a stereoselective fashion involving metal mediated fragmentation, stereoselective reduction, 1,4 O → O silyl migration, and Grubbs' cross metathesis as key steps. d-Fructose was used as a raw material for the preparation of all the analogues. The isophytosphingosine derivatives were evaluated against their 5-LOX (5-lipoxigenase) inhibitory activity.